Investigators propose to study the practicality of using MRI to determine the extent of congenital diaphragmatic hernias (CDH) in the fetus. Currently, ultrasonographic means are used to determine the extent of liver herniation and the impact this has had on lung growth in the fetus with CDH. This method is very user dependent and currently only being performed by ultrasonographers at UCSF. A method that is reproducible and accurate would aid in identifying patients that would benefit from fetal intervention. Under this protocol, patients that are already in the UCSF system obtaining evaluation of their CDH would undergo MRI evaluation and the two results compared for similarity and accuracy. MRI evaluation will also allow us to compute lung volume versus the currently available lung cross sectional area. This newly computed lung volume will be studied to evaluate its potential use as a prognostic indicator. Usefulness as a prognostic indicator is key in this population as prognosis directly affects treatment plans.